Guide arm and cradle for the upper
apron of a double apron drafting ar-
rangement



May. l7, 1966 A. SCHILTKNECHT 3,251,099

GUIDE ARM AND CRADLE FOR THE UPPER APRON OF A DOUBLE APRON DRAFTING ARRANGEMENT Filed Aug. 19, 1963 INVENTOR. /7Do/.F Sum rmvawr The present invention relates to the combination of a guide arm with a cradle for the upper apron of a double apron drafting arrangement of a spinning machine. In double apron drafting arrangements for drafting fibre material of great staple length cradles of great length are required. The conventional cradles rest on either side of the top rolls and are usually guided by saddles which are swingably accommodated in a'guide arm. Long cradles cause considerable moments which tend to swing the cradles and particularly the apronreversing elements thereof out of their parallel position with the drafting rollers. Due to unavoidable clearances the aforesaid moments cause the cradles to assume a slanted position in the plane of the drafting field whereby the movement of the apron is adversely affected.

It is an object of the present invention to provide a combination of a guide arm with a cradle for the upper apron of a double apron drafting arrangement whereby the movement and position of the aprons are accurately controlled, even in case of unusually long drafting fields. In the arrangement according to the invention the cradle laterally abuts against the guide arm and is accurately guided in the plane of the drafting field and is swingable in a part plane normal to the drafting field. Guidance of the cradle by the guide arm is preferably effected by providing the cradle with lateral protuberances which project toward and engage with vertical lateral surfaces of the guide arm.

Since guidance of the cradle is effected directly on the guide arm, accurate parallelism of the apron-reversing elements with the drafting rolls is assured and the top roll whereon the cradle rests is accurately held in the predetermined position. The greater the distance between the locations where the cradle is guided the greater is the accuracy of maintenance of the position of the cradle. With long cradles this distance considerably exceeds the width of the guide arm and accuracy of the assembly is definitely assured. With the arrangement according to the invention fits placed in series relatio whose tolerances are added up, are avoided.

The novel features which are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, and additional objects and advantages thereof will best be understood from the following description of an embodiment thereof when read in connection with the accompanying drawing wherein:

FIG. 1 is a diagrammatic part-sectional side view of a guide arm and cradle arrangement according to the invention.

FIG. 2 shows a section of the arrangement shown in FIG. 1, the section being made along line IIII of FIG. 1. FIG. 3 shows a part section of the arrangement shown in FIG. 1 and made along line IIIIII of FIG. 1.

Referring more particularly to FIGURES 1, 2 and 3 of the drawing wherein like parts are designated by like numerals, numeral 1 designates a guide and weighting arm having an inverted U-shaped cross-sectional con- United States Patent figuration. This arm carries a twin .top roll 2 including a connecting shaft 3 whereon rests a cradle 5 for an upper apron 14. The cradle 5 is provided with suitable recesses 4 for receiving the shaft 3. The cradle 5 comprises a U-shaped frame 7 having lateral walls 6. The frame 7 has lateral extensions 8 to which outwardly acting resilient apron guides 9 are connected. An apronreversing roller 10 is mounted on the forward end of the cradle. The walls 6 extend outside of and beyond the lower edges of the lateral walls 11 of the guide arm 1 when the assembly is in operating position. The walls 6 are provided with bosses 12 and 13 extending toward the walls 11. The bosses 12 and 13 are as widely spaced as possible and slidingly engage with the walls 11, permitting swinging of the cradle in a plane normal to the plane of the drawing field. The bosses, however, definitely prevent swinging of the cradle parallel with the plane of the drawing field. With the arrangement according to the invention the long cradle 5 is accurately held in the desired position without hindering swinging of the cradle around the axis of the twin top roll.

' I claim:

1. In a double apron drafting arrangement for spinning machines means defining a plane drafting field and including an upper apron,

a guide arm having a pair of opposed surfaces,

a top roll carried by said guide arm and forming part of said. means defining a plane drafting field, said apron surrounding said top roll,

a cradle for said upper apron, said cradle having a pair of walls opposite said .opposed surfaces and a portion resting on said top roll,

at least one of said walls and one of said opposed surfaces being vertical, and

means provided on each of said walls for slidably engaging a respective one of said surfaces for affording movement of said cradle relative to said guide arm and in a plane normal to the plane of said drafting field and preventing movement of said cradle in a plane parallel with the plane of said drafting field.

2. In a double apron drafting arran'gement for spinning machines means defining a plane drafting field and including an upper apron,

a guide arm having a pair of oblong opposed surfaces,

at top roll carried by said guide arm and forming part of said means defining a plane drafting field, said apron surrounding said top roll,

an oblong cradle for said upper apron, said cradle having a pair of walls opposite said opposed surfaces and a portion resting on said top roll,

at least one of said walls and one of said opposed surfaces being vertical, and

means provided on each of said Walls for slidably engaging a respective one of said surfaces for affording movement of said cradle relative to said guide armin a plane normal to the plane of said drafting field and preventing movement of said cradle in a plane parallel with the plane of said drafting field.

3. In a double apron drafting arrangement as set forth in claim 2 wherein said means provided on each of said walls comprises a plurality of bosses projecting toward said opposed surfaces, said bosses being arranged in longitudinal manner with repect to said walls.

4. In a double apron drafting arrangement for spinning machines,

means defining a plane drafting field including an upper apron,

9 4 a a guide arm having lateral vertical surfaces, References Cited by the Examiner a top roll carried by said guide arm and forming part UNITED STATES PATENTS of said means defining a plane draftlng field, said 2,751,631 6/1956 Hunter et a1. 19-252 X apm SJrmmdmg Smd roll and 2,890,495 6/1959 Miesch et a1 19-261 a cradle for said upper apron, said cradle having a 5 portion resting on said top roll and including means FOREIGN PATENTS slidably engaging said vertical surfaces and afford- 1,093,? 13 11/1960 Germany. ing movement of said cradle relative to said guide 578,159 6/1958 Italy. arm in a plane normal to the plane of said drafting field and preventing movement of said cradle in a 10 DONALD R Prlmmy Examiner plane parallel with the plane of said drafting field. D. NEWTON, Assistant Examiner. 

1. IN A DOUBLE APRON DRAFTING ARRANGEMENT FOR SPINNING MACHINES MEANS DEFINING A PLANE DRAFTING FIELD AND INCLUDING AN UPPER APRON, A GUIDE ARM HAVING A PAIR OF OPPOSED SURFACES, A TOP ROLL CARRIED BY SAID GUIDE ARM AND FORMING PART OF SAID MEANS DEFINING AS PLANE DRAFTING FIELD, SAID APRON SURROUNDING SAID TOP ROLL, A CRADLE FOR SAID UPPER APRON, SAID CRADLE HAVING A PAIR OF WALLS OPPOSITE SAID OPPOSED SURFACES AND A PORTION RESTING ON SAID TOP ROLL, AT LEAST ONE OF SAID WALLS AND ONE OF SAID OPPOSED SURFACES BEING VERTICAL, AND MEANS PROVIDED ON EACH OF SAID WALLS FOR SLIDABLY ENGAGING A RESPECTIVE ONE OF SAID SURFACES FOR AFFORDING MOVEMENT OF SAID CRADLE RELATIVE TO SAID GUIDE 